Monitoring systems with capabilities to monitor the protocol health of mobile device networks, for example vehicle networks, are known in the prior art. Monitoring systems that provide useful protocol health information are also known in the prior art.
U.S. Pat. No. 8,213,321 B2 issued on Jul. 3, 2012 to Butts and Anderson and is assigned to Deere & Company. This patent relates to a method and system to monitor a communications network such as a controller area network (CAN) and more specifically, an in-vehicle communications network, by maintaining a count of each type of error code and a histogram of all network messages seen by each of the controllers during a measurement period; and by determining a bus health index of the communication bus based upon a percentage of a given type of error to the total count of all errors during a measurement period. An individual controller or controller area network bus segment can be indicated as having a communications problem because of the health index.
United States PCT patent application US2012/053725 published on Mar. 13, 2014 to Zhang et al. and is assigned to GM Global Technology Operations LLC. This patent application relates to a controller area network (CAN) that has a plurality of CAN elements including a communication bus and controllers. A method for monitoring the controller area network CAN includes identifying active and inactive controllers based upon signal communications of the communication bus and identifying a candidate fault associated with one of the CAN elements based upon the identified inactive controllers.
U.S. Pat. No. 8,799,738 B2 issued on Aug. 5, 2014 to Emde et al., and is assigned to Robert Bosch GmbH. This patent relates to a method of detecting data transmission errors in a CAN controller including generating at least one check bit that is verifiable for ensuring the consistency of the transmitted data. A CAN controller that ensures continuous error monitoring during data transmission includes an interface unit for exchanging data with a CAN bus, a memory unit for storing received data and data to be transmitted, and an electronic unit for controlling data transmission between the memory unit and the interface unit. The interface unit of the CAN controller has an arrangement for generating check bits for received data and for verifying check bits for data to be transmitted.
U.S. Pat. No. 6,795,941 B2 issued on Sep. 21, 2004 to Nickels and is assigned to Honeywell International Inc. This patent relates to a network having at least one controllable CAN-based sensor device having a microcontroller, a power source and at least one host controller. Preferably, the network is a Smart Distributed System-based network. In this embodiment, each microcontroller communicates with the controller, generating and storing a value in at least one counter when a successful message is transmitted to the controller. When a unsuccessful message is detected by the microcontroller, a counter generates and stores a second or decremented value in the same or different counter. When the sum total value of error messages in the counter reaches a marginal critical value, a message is transmitted to the controller while maintaining the microcontroller's communication with the network. When a counter reaches a critical value, the microcontroller enters a bus off mode and disconnects the sensor device, and thus the microcontroller, from the network.
The prior art approaches and in particular the approaches to monitoring the protocol health of vehicle controller area networks and providing useful protocol health information are deficient.